Propeller



PATENTED FEB. 23, 1904.

E. D. HAMILTON.

PROPELLBR. APPLICATION 31mm OUT. 31, 1903.

I N0 MODEL.

avwewtoz Patented February 23, 1904.

UNITED STATES PATENT OFFICE.

EDWARD D. HAMILTON, OF VANCOUVER, WASHINGTON.

PROPELLER.

SPECIFICATION forming part of Letters Patent No. 752,670, dated February 23, 1904. Application filed 0ct0ber 31, 1903. Serial No- 179,354=. (N0 model.)

To all whom it may concern:

Be it known that I, EDWARD D. HAMILTON, acitizen of the United States, residing at Vancouver, in the county of Clark and State of Washington, have invented new and useful Improvements in Propellers, of which the following is a specification.

This invention relates particularly to the form and construction of screw-propellers; and the object thereof is to improve the same with respect to the means for attaching the blades to the shaft.

A further object is to provide a propellerblade of improved shape so constructed and attached to the shaft that it may be readily removed and replaced.

Further special advantages will be apparent from the following description and claims.

In the accompanying drawings, Figure 1 is an end view of the propeller.v Fig. 2 is a side view thereof. Fig. 3 is a perspective view of the end of the main shaft with the blades and hub removed, and Fig. 4 is a similar view showing a rounded shaft instead of a squared shaft.

Referring specifically to the drawings, the end of the main shaft is indicated at 6, and this end may be squared, as indicated in Fig. 3, or rounded, as indicated in Fig. 4. On the several sides thereof, according to the number of blades, it has lengthwise undercut or dovetailed gains or mortises 7, which commence at the end of the shaft and end in shoulders 8, against which the hub abuts and. which receive the thrust of the screw. Upon the end of the shaft is fitted the hub or strengthening-band 9, which is in width substantially equal to the length of the mortises and which has dovetailed tenons 10, which fit within the mortises, and opposite these tenons the hub or strengthening-band is likewise gained or mortised to receive the base 11 of the blade 12.

The blade comprises a metal plate the lower end of which is forged or bent at an angle to form the base 11, from one edge of which the blade proper rises, the shank at 13 being twisted to give the proper or desired pitch to the blade. The plate from which the blade is made is of substantially equal Width throughout, giving in comparison to the blade a broad base 11. Bolts 14, extending through the base of the blades, the hub, and the shaft, securely fasten the parts together.

When the parts are assembled, the hub and blades abut against the shoulders 8, which.

thus receive the thrust of the screw and prevent loosening of the screw by pressure. The dovetailed construction takes and supports the lateral thrust, and owing to the width of the shanks 13 there is little liability of the blades breaking off at the shanks.

Should a blade become broken, it is a simple matter to remove the bolt and knock it out and substitute another blade in place.

What I claim as new, and desire to secure by Letters Patent, is-

1. The combination with a shaft having dovetailed mortises therein, of a hub having on the inside tenons fitting said mortises and on the outside similar dovetailed mortises, and lfilades having bases fitting the mortises inthe 2. The combination with a shaft having lengthwis e'dovetailed mortises extending from the end of the shaft to shoulders, of the hub having on the inside tenons fitting said mortises and abutting against the shoulders, and blades secured to the hub.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

EDWARD D. HAMILTON.

Q Witnesses:

J. W. HOPKINS, JAMES CRAWFORD. 

